Additional DNSMasq Options

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The "Additional DNSMasq Options" is an optional setting in the tab: Services > Services.

[edit] DHCP Options

  • DHCP-Authoritative should be set when DD-WRT is the only DHCP server on its network segment (the most common setup). When authoritative, the DHCP server will immediately assign new addresses to clients that try to register using IPs from another network (rather than letting their previous lease time run out).
    • See also: -dhcp-authoritative in the man page, forum thread
  • RFC4039 Rapid Commit support removes a round trip by returning an address lease in response to a DHCPDISCOVER from a client that also supports Rapid Commit.

[edit] DNS Options

  • Forced DNS redirection redirects all DNS requests on port 53 to DD-WRT's internal DNSmasq server, even if those requests were pointed directly at an external DNS server. Note that, as discussed in the forum thread, savvy users might still be able to communicate with external DNS servers on non-53 ports.
  • Validate DNS Replies (DNSSEC) requests and validates DNSSEC records for domains that have them, if supported on your router model.
  • Check unsigned DNS replies also checks that unsigned DNS replies are legitimate (they belong to domains that actually do not publish DNSSEC records).
    • See also: --dnssec-check-unsigned in the man page
  • Cache DNSSEC data copies the DNSSEC Authenticated Data bit from the upstream server. This option is available on some hardware that does not support direct DNSSEC validation, but it should only be used when the upstream server is trustworthy. Cache size 0 is recommended when using this option.
    • See also: --proxy-dnssec in the man page
  • No DNS Rebind rejects IP address responses in the private IP ranges from upstream (i.e. public) DNS servers.
    • See also: --stop-dns-rebind in the man page, ext link on security implications
  • Query DNS in Strict Order tells DNSmasq to query the upstream servers in the order entered, i.e. 1 first. Otherwise, queries can go to any upstream server.
    • See also: --strict-order in the man page
  • Add Requestor MAC to DNS Query adds the internal requestor's MAC address to the query sent to the upstream DNS server, which could be necessary if the upstream server filters requests by MAC.
  • Maximum Cache Size sets how many names DNSmasq stores in its cache (default 150).
    • See also: --cache-size in the man page

currently I (Jackykoning) only know one fun trick that might be useful for some people.

This redirects the stupid babylon search engine to google.


prefix = address=/"url here"(without http:// and without /shit )/"ip here" (not another url!)

[edit] External Links